The Secret of Mirror Bay is the forty-ninth volume in the Nancy Drew Mystery Stories series, published in 1972 under the pseudonym Carolyn Keene.The Secret of Mirror Bay at WorldCat
Plot summary
Aunt Eloise invites Nancy and her friends to a cabin at Mirror Bay, in Cooperstown, New York, to solve a case of a mysterious woman seen gliding across the water. Nancy is then involved in a vacation hoax because she resembles a woman involved in the hoax. A strange green sorcerer who appears in the woods and a lost treasure involving the gliding woman lead Nancy and her friends to uncover a concealed operation in the woods.
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